Broach



Mar. 13, 1923,

I A. 1. UTZINGER.

BROACH. l

FILED ocT. 30. 1920.

IN VEN T01? ity of series of cuttino' Patented Mar. 13, 1923,.

AUNITED STATES-PATENT oFFlcE..

ARTHUR J'. UTZINGER, OF PLAINFILD, NEW JERSEY, ASSIGNOR T0 INTERNATIONAL MOTR COMPANY, OF NEW YORK, N. Y., A. QRPORVATION 0F DELAWARE Pacem- Appneauon mea' qgtotr so, 1920. serial No. 420,004.

To all whom,- z't mag/concem:

Be it known that I, ARTHUR J. U'rzlNoER, a citizen of the United States, residin in the city of Plainfield, in the State of ew Jersey, have invented certain new and useful Improvements in Broaches, of which the following is a specification, reference being` had to the accompanying drawing, forming a part hereof.

This invention relates to breaching tools and has reference particularly to suc tools as are constructed for breaching oil grooves orAkey-ways in gears. Heretofore it has been the practise to cut the breaching teeth intenfral with the body of the tool and then hardening the unit. Breakage or wear of any one of the many teeth has 4reduced the effective operation of such tools and .usually required them to be discarded. The cost of such practise, not to speak of the inconvenience and loss of time in replac' ing discarded tools with new ones, has been very great. The object of the present invention is to provide a breach of the character described inV which the breaching teeth er cutting pieces are formed as separate units of high speed hardened steel which are adjustably and removably supported within the body of the breach this body being, in the preferred form, of soft steel. The improved construction permits the ready removal or adjustment of any one of the separate breaching teeth so that the operator always has within his determinat-ion the height'and eiectiveness of any one of said teeth. Further, the pro osed tool lends itself to the provision of a p uralpieces displaced angularly about the bodyand, if necessary, disposed in staggered relationship to give ample clearance for the adjusting and `securing means for the individual teeth. Reference is new to be had to the accompanying drawing for a detailed description of a preferred embodiment of the invention, in which- Figure 1 is a view in elevation of a fragment of a broach showing two series of cuttingV teeth secured removably within the bo 1 Figure 2 is a view in end elevation of the tool shown 1n Figure 1.

. Figure 3 1s a v1ew in transverse sect1on through the body taken on the' plane indi-v -nte by the line 3--3 of Figure 1 and look- 55 mijn the direction of the arrows.

igure 4 shows a fragment of the body ofthe breach with a tooth and'its retaining devlces removed therefrom.

- Figures 5 and 6 are detail views on an en- 60 larged scale of a suitable type of tooth.

As pointed out heretofore, it has been the usual practise to cut the teeth of aNbroachv integral with t-he body and then harden the tool thus formed. Broaching tools for cutting oil glrooves and key-ways are usually formed wit a series of teeth of gradually increasing height arranged to make successive cuts as the tool is passed through the work. The breakage or wear of any one of the teeth, of a serles necessarily interrupts the sequence of effective cutting operations. Indeed, when any one of the teeth of a series thus becomes ineffective it is usually necessary to discard 'the entire tool. The 75 improved breach illustrated in the drawing comprises a body a carrying, inl the preferred form, three series of teeth disposed longitudinally thereof and displaced about the periphery at equi-distant angles, one series of teeth being indicated at b, b1, b2, b3; another series at c, Vc1, c2, c3 and the third series in dotted lines in Figure 1 at al. d1, d2. The invention is not to be limited to the number of teeth nor to the number of series, since each of the teeth is mounted by the same means; .a description of means for one such tooth, such as b2 (Figure 3)` will be suiicient for an understanding of the construction. The body of the breach a, which is preferably of soft steel, is drilled through diametrically to rovide -a channel a1 to receive the shank o the tooth b* and which may be of any approved cross-sectional form, dependin on the form of the shank of the tooth. he channel a1 which receives the shank of the tooth communicates with an internally threaded bore a in which is threaded a set screw e. The body of the breach a is drilled in, as at a4,.at an angle of 90 to the recess a1 and threaded to receive a lockingl screw f, the inner end of which can be moved into locking engagement with the side of the shank of the tooth b2. The channelsa:3 and a* are counter- 105 sunk to leave the heads of the screws e, f, within' the periphery of the body 'a of the breach. I

. speed hardened steel and each of these teeth has its vown separate securing and adjusting'y screws corresponding to the screws e, f, respectively, whereby the height of thet'oth above the body of the broach, which deter'- mines the cut of the particular tooth, can-bereadily fixed bythe operator. A tooth which becomes worn can be raised by looseniin the set screw f and' threading in the a justing screw e until the tooth, such as b2, 1s given the desired height, whereupon the locking screw f can beset up against its shank. Where three series of teeth are employed, as illustrated in Figure 1, it will preferably be desirable to stagger the corresponding teeth b, c, d, of the different series, so that the drillings through the body a of the broach to receive the respective teeth and their adjusting and locking devices will not intersect.

The construction is initially. inexpensive and insures the provision of a tool which can 'be kept in continuous operation, the body a of the broach not being subjected to any disintegrating action and all ofthe teeth,

as appears, being susceptible of ready re- A placement or adjustment as maybe necessallly.

claim as my invention:

1. 'As an article of manufacture, a cylinv drical breaching tool having a body formed with aplurality of rows of openings displaced angularly about the tool to receive lremovable cutting pieces, adjusting screws threaded in the body opposite said openin s respectively to bear on the rear ends of t 1e cutting pieces to force them outwardly, and locks screw threaded in at right angles to the cutting pieces respectively to clamp them y in adj usted posit-ion.

2. As an article of manufacture, a breach ing tool having a body formed with longitudinal rows of independent slots and a plurality of separate cutting pieces of equal length mounted removably and adjustably in the slots, the slots for the cutting pieces of the several rows being staggered circumferentially with relation to one another to stagger the cutting pieces.

This specification signed this 26 October, A. D. 1920.

ARTHUR J. UTZINGER.

day ot' 

